<template>
  <footer class="footer">
				<!-- This should be `0 items left` by default -->
				<span class="todo-count"><strong>{{unDoneTodoLength}}</strong> item left</span>
				<!-- Remove this if you don't implement routing -->
				<ul class="filters" @click="$emit('switchTodo',type)">
					<li>
						<a :class="{selected:type==='all'}" href="#/" @click="type='all'">All</a>
					</li>
					<li>
						<a href="#/active" :class="{selected:type==='no'}" @click="type='no'">Active</a>
					</li>
					<li>
						<a href="#/completed" :class="{selected:type==='yes'}" @click="type='yes'">Completed</a>
					</li>
				</ul>
				<!-- Hidden if no completed items are left ↓ -->
				<button class="clear-completed" v-if="hasDoneTodo" @click="clear">Clear completed</button>
			</footer>
</template>

<script>
export default {
	data(){
		return{
			type:'all'
		}
	},
	props:['arr'],
	computed:{
		unDoneTodoLength(){
		return	this.arr.filter(item=>item.isDone===false).length
		},
		hasDoneTodo(){
			return this.arr.some(item=>item.isDone===true)
		}
	},
	methods:{
		clear(){
			if(confirm('确定要删除已完成的项目吗?')){
				this.$emit('clearTodo')
			}
		}
	}
}
</script>

<style>

</style>
